import coordinates: cannot import name sofa_time

I have installed astropy-0.2 on a mac.

```
from astropy import coordinates  gives these errors:
RROR: ImportError: cannot import name sofa_time [unknown]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "astropy/coordinates/__init__.py", line 14, in <module>
    from .builtin_systems import *
  File "astropy/coordinates/builtin_systems.py", line 12, in <module>
    from ..time import Time
  File "astropy/time/__init__.py", line 2, in <module>
    from .core import *
  File "astropy/time/core.py", line 25, in <module>
    from . import sofa_time
ImportError: cannot import name sofa_time
```

my python version info is:

```
Python 2.7.3 |EPD 7.3-2 (64-bit)| (default, Apr 12 2012, 11:14:05)
[GCC 4.0.1 (Apple Inc. build 5493)] on darwin
```

I am using MacOS Mountain Lion: 10.8.2